Queen Elizabeth II´s sixth great-grandchild on the way

London: Queen Elizabeth II´s sixth great-grandchild is on the way, after Zara and Mike Tindall announced Wednesday they were expecting a second baby.

The 90-year-old monarch and her husband Prince Philip are "delighted", Buckingham Palace said.

Zara Tindall, the sovereign´s eldest grand-daughter, is an equestrian who won the 2006 eventing world championships and a silver medal for Britain at the London 2012 Olympics.

The 35-year-old daughter of Princess Anne has no title and does not carry out royal duties.

Mike Tindall, 38, is a former England rugby captain who was in the 2003 World Cup-winning squad. The couple married in Edinburgh in 2011.

Their first child, daughter Mia, was born in January 2014.

A spokeswoman for the Tindalls said: "Mike and Zara are expecting another baby" and the couple were "thrilled".

The new baby will be 18th in line to the throne.

"The Queen and the Duke of Edinburgh and members of the royal family are delighted with the news," a palace spokesman said.

Tindall said on Twitter afterwards: "Just a quick one to say thank you for the messages. We are very very happy about the little one on its way. 2017 is already starting well!"

The Tindalls live on Anne´s Gatcombe Park country estate in Gloucestershire, southwest England.

Queen Elizabeth´s five great-grandchildren so far are Prince William´s children, Prince George and Princess Charlotte; Savanna and Isla Phillips, the daughters of Zara´s brother Peter; and Mia Tindall.

The queen sat with all five earlier this year in a photograph by Annie Leibovitz.

Mike Tindall once revealed that George´s first meeting with Mia was "carnage", with most of the prince´s food going on the table rather than in his mouth.